This study examined the developmental significance of mothers' adult attachment representations assessed prenatally with the Adult Attachment Interview in relation to observed maternal sensitivity at 6 months postpartum in an ethnically diverse sample (N = 131 African American; N = 128 European American). Multiple‐group confirmatory factor analyses provided evidence for partial measurement invariance of a two‐factor dismissing and preoccupied latent structure of adult attachment across the two ethnic groups of women. African American women showed modest elevations on the preoccupied factor relative to European American women. Although the dismissing factor showed an empirically equivalent negative association with maternal sensitivity in both ethnic groups, this effect was reduced to marginal significance when controlling for maternal socioeconomic status.